This is the size for a typical household's 7-person septic tank. Fujikleen ★ Blower for Septic Tanks Electromagnetic Air Pump ★ Diaphragm for Septic Tanks EcoMac40. Blower for Septic Tanks Air Pump Diaphragm for Septic Tanks 【Main Specifications】 Voltage: AC100V Rated Frequency: 50/60Hz Rated Power Consumption: 32W Operating Pressure: 12kPa Airflow: 40 L/min I think it can be used for aeration of septic tanks and water tanks. This item was used outdoors for a household single septic tank. As it is an outdoor product, there are some scratches and dirt that cannot be removed. We appreciate your understanding of the current condition. ※ Operation has been confirmed, disassembled and cleaned. Please consider this for septic tank and aquarium air pumps. Septic Tank Air Pump Septic Tank Blower Septic Tank Pump Septic Tank Air Pump Hitachi Blower Housetec Air Compressor Fujikleen Kogyo Co., Ltd. Discharge Port Diameter: φ18 (VP13) Widely used for septic tanks / aquaculture ponds / ornamental fish tanks / industrial equipment. #Agitation #Medaka (Japanese rice fish) #Aquaculture #SepticTank #Hydroponics #EnergySaving #Goldfish #Blower #AirPump #AirPump